IRG-III Highlight
Figure. (a) Semiconductor nanofilaments extracted from fiber by dissolving the polymer matrix. (b) SEM micrograph of a Se filament and a magnified section of it. (c) (i) A bundle of As2Se3 filaments. (ii) Magnified section showing parallel filaments. (iii) A section of a single filament. |
A new process for creating in-fiber semiconductor filament arrays
Authors: John D. Joannopoulos (MIT), Yoel Fink (MIT), H.A. Stone (Harvard) and A.F. Abouraddy (U. Central Florida)
Professors Joannopoulos and Fink of IRG-III report an intriguing phenomenon in which a semiconductor cylindrical shell (inside of a fiber preform) undergoes a scaling process and evolves into an array of filaments, once the preform is drawn into a fiber. The length of the nanofilaments produced with this method is especially captivating. For example, the semiconductor film in a typical fiber preform is 10-cm long, 3-cm wide and hundreds of nanometers in thickness. From this preform, forty meters of fiber may be produced if it is drawn down by a scaling factor of 20. The number of filaments in the fiber is around 100. Thus, hundreds of meters long filaments can be produced from a single semiconductor sheet clad in a polymer preform. Hundreds of glassy semiconductor filament arrays are precisely oriented within a polymer fiber matrix, as shown in the figure. This approach will enable, for the first time, the creation of fibers with a high density of electrical interconnects, that may be potentially useful in enabling diverse large-area devices for renewable energy (photovoltaics, thermoelectrics) and bioengineering (scaffolding for tissue growth) applications.
“In-fiber semiconductor filament arrays.” D.S. Deng, N.D. Orf, A.F. Abouraddy, A.M. Stolyarov, J.D. Joannopoulos, H.A. Stone and Y. Fink. Nano Letters 8(12), 4265–4269 (2008).
This work was supported in part by the NSF MRSEC Program (award number DMR - 0819762).
